Great Bitter Lake

The basin later occupied by the Great Bitter Lake lay in the Suez isthmus between Egypt's Mediterranean and Red Sea approaches. Before the nineteenth-century maritime canal flooded it, the basin was dry and contained extensive deposits of salt. Its early modern landscape differed greatly from the open water and shipping anchorages created by the later canal.

The wider isthmus attracted renewed engineering interest during the French occupation of Egypt in 1798–1801. Napoleon's surveyors investigated the possibility of joining the seas, but erroneously concluded that the Red Sea stood substantially higher than the Mediterranean. Plans therefore remained separate from an operating waterway. The Bitter Lakes depression belonged to the terrain that engineers had to understand and cross: low ground and salt deposits formed part of a land barrier whose conversion into navigable water still lay beyond the period.